Heat recoverable sleeves have found widespread application in protection and sealing of wire bundles.
Heat recoverable articles are well known. They are articles the dimensional configuration of which may be made substantially to change when subjected to heat treatment. Usually these articles recover, on heating, towards an original shape from which they have previously been deformed; but the term "heat recoverable," as used herein, also includes an article, which, on heating, adopts a new configuration, even if it has not been previously deformed.
During the handling of electrical harnesses, particularly in automotive applications, wire insulation is sometimes nicked or otherwise damaged and must be repaired or replaced. The most common procedure is to repair the damage by cutting the wire at the damage site, stripping insulation from the wire, splicing the ends, covering the joint and heating to insulate and seal. This process is time consuming and produces a final product which is often bulky, inflexible and does not meet the quality standards specifications.
Attempts have been made to provide sleeves which may be installed at any point along a line without requiring access to its end, as is typically required with the use of tubes or sleeves. The problem most commonly encountered in constructing and installing such a wrap around or side entry article is the provision of a closure device capable of withstanding the considerable shrinkage forces exerted during recovery, and yet simple enough to be manufactured and used in a practical manner. Typical wrap around articles are also difficult to handle and install, tending to unwrap around the wire bundle while closure is effected, taking considerable time and skill. Examples of wrap around type heat recoverable articles can be found in U.S. Pat. Nos. 4,900,596; 4,865,890; 4,860,799; 4,795,509; 4,735,836; 4,731,271; 4,699,821; 4,560,828; 4,518,448; 4,442,155; 4,280,258; 3,959,052; 3,899,807; 3,847,721 and 3,770,556; International Publication WO 94/27299; Great Britain Patent Application 2 043 729 and German Patent Application 40 32 376 which are hereby incorporated by reference for all purposes.